Systems, methods of use and surgical instruments employing a secure slide lock to fasten a head

ABSTRACT

A system comprising surgical instruments of different types. Each surgical instrument includes a body member and a leg having a first end integrated with and a leg portion extending from the body member. The instrument includes a head cavity formed in a free end of the leg. The cavity holds a head. A channel is formed along a portion of a longitudinal length of the leg. The instrument includes an elongated rocker assembly pivotally coupled within the channel, with a spring actuation tab in proximity to the body member. The instrument includes a collar slidably coupled around the body member and having a first position located between the body member and the actuation tab such that a portion of the collar is under the actuation tab to limit pivotal motion of the rocker assembly and a second position of the collar has a clearance from under the actuation tab.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.16/850,385, filed Apr. 16, 2020, which is incorporated herein byreference in its entirety.

FIELD

The present technology is generally related systems and methods of useand surgical instruments such as extenders and derotators that securespinal constructs including bone fasteners and connectors for treatingthe spine.

BACKGROUND

Spinal disorders of the spine may result in symptoms, such as withoutlimitation, nerve damage, and partial or complete loss of mobility andchronic pain. Surgical treatment of these spinal disorders includescorrection, fusion, fixation, discectomy, laminectomy and implantableprosthetics, for example. As part of these surgical treatments,vertebral rods and bone fasteners are often used to provide stability toa treated region. During surgical treatment, a surgeon uses varioussurgical instruments, such as extenders, reducers and derotators, toimplant one or more rods and bone fasteners to a surgical site.Extenders, for example, are used with reducers to implant a rod.

This disclosure describes an improvement over these prior arttechnologies.

SUMMARY

The techniques of this disclosure generally relate, for example, tosystems and method, for example, using instruments with a rocker slidelock that when locked and/or connected reduces the likelihood of and/orprevents a head-locking projection for securing a head of the bonefastener from becoming inadvertently disengaged. The surgicalinstrument's configuration may maintain a minimum profile as theelongated rocker assembly is moved into an engaged position and/ordisengaged position.

In one aspect, the present disclosure provides a system that may includea plurality of surgical instruments of different types. Each surgicalinstrument may include a body member having a top end and a bottom end.Each instrument may include a leg having a first end integrated with anda leg portion extending from the body member. A head cavity may beformed in the leg portion and may be configured to hold a head. Eachinstrument may include an elongated channel formed along the leg and anelongated rocker assembly pivotally coupled within the channel, with aspring actuation tab in proximity to the body member. A collar may beslidably coupled around the body member. The collar may include a firstposition located between the body member and the actuation tab such thata portion of the collar may be under the actuation tab to limit pivotalmotion of the rocker assembly and a second position of the collar has aclearance from under the actuation tab.

In various aspects, the instruments may include reducers of differentsizes. The instruments may include a derotator.

In another aspect, the disclosure provides a method that may includeproviding a plurality of reducers and coupling a respective one reducerto a respective one surgical instrument to form an instrument assemblywith a rocker slide lock. The method may include using the instrumentassembly for reducing a rod in a head of a bone fastener and prior toreducing the rod, locking and/or connecting the head with rocker slidelock.

The details of one or more aspects of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the techniques described in this disclosurewill be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a perspective view that illustrates components of universalsurgical implant system.

FIG. 1B is a perspective view that illustrates some components of theuniversal surgical implant system being linked together.

FIG. 2 is a perspective view that illustrates a short open-extenderinstrument assembly.

FIG. 3 is a perspective view that illustrates a long open-extender.

FIG. 4 is a perspective view that illustrates a short closed-extenderinstrument assembly.

FIG. 5 is a perspective view that illustrates a long closed-extender.

FIG. 6 is a perspective view that illustrates a long reducer.

FIG. 7A is a perspective view that illustrates a short instrumentadapter.

FIG. 7B is a perspective view that illustrates a short instrumentadapter with the lever and spring separated.

FIG. 8A is a perspective view that illustrates a shank-extenderinstrument assembly.

FIG. 8B is an exploded view of interior components of the shank-extenderinstrument assembly of FIG. 8A.

FIG. 9A is a perspective view that illustrates an apical derotator.

FIG. 9B is a side view that illustrates an apical derotator of FIG. 9A.

FIGS. 10A-10B are front and back views that illustrate the shortopen-extender instrument assembly of FIG. 2.

FIGS. 11A-11B are perspective views that together illustrate an explodedview of the short open-extender instrument assembly of FIG. 2.

FIG. 11C is a perspective view that illustrates a rear side of the shortclosed-extender.

FIG. 12A is a side view that illustrates the short open-extenderinstrument assembly of FIG. 2 in an engaged and unlocked state.

FIG. 12B is a side view that illustrates the short open-extenderinstrument assembly of FIG. 2 in an engaged and locked state.

FIG. 13 is a cross-sectional view along the plane of 13-13 in FIG. 12B.

FIG. 14A is a cross-section view of along the plane 14A-14A in FIG. 13.

FIG. 14B is a cross-section view of along the plane 14A-14A in FIG. 13with instrument in unlocked and disengaged position.

FIG. 15 is a side view that illustrates a profile of the elongated leverarm.

FIGS. 16A-16C are front, side and rear views of the shortclosed-extender instrument assembly of FIG. 4.

FIG. 17A is a perspective view of the second reducer pusher for theshort reducer.

FIG. 17B illustrates top perspective view of the first reducer pusherfor the short reducer.

FIG. 18 is an end view of the derotator of FIG. 9A.

FIG. 19 is a side view that illustrates a prior art bone fastener.

FIG. 20A is a perspective view that illustrates the shank-extenderinstrument assembly of FIG. 8A and a bone fastener.

FIG. 20B is a cross-sectional view along the plane 20B-20B of FIG. 20A.

FIG. 20C is a cross-sectional view, as shown in FIG. 20B, with the bonefastener attached to the shank-extender instrument assembly in anextended position.

FIG. 20D is a cross-sectional view, as shown in FIG. 20B, with the bonefastener attached to the shank-extender instrument assembly in aretracted position.

DETAILED DESCRIPTION

The embodiments of the universal surgical implant system are discussedin terms of medical devices for the treatment of musculoskeletaldisorders and more particularly, in terms of a surgical system and amethod for treating a spine. In the embodiments, the system may includea surgical instrument that may include a rocker slide lock to, forexample, lock a head-locking projection in a bone fastener nestled inthe head cavity, and the related methods of use that can be employedwith spinal constructs including bone fasteners and connectors thatprovide a universal surgical implant system for spine surgeons. Therocker slide lock when locked may, for example, reduce the likelihood ofor prevent a head-locking projection for securing a head (e.g.,polyaxial head, uni-axial head, monoaxial head, etc.) of the bonefastener from becoming inadvertently disengaged. The surgicalinstrument's configuration may maintain a minimum profile as theelongated rocker assembly is moved into an engaged position and/ordisengaged position.

In some embodiments, the system may include an extender and derotatorthat are configured with a rocker slide lock to lock and/or connect ahead-locking projection in a head (e.g., polyaxial head, uni-axial head,monoaxial head, etc.) of a bone fastener nestled in the head cavity, andthe related methods of use that can be employed with spinal constructsincluding bone fasteners and connectors that provide a universalsurgical implant system for spine surgeons. The extender's configurationand derotator's configuration maintain a minimum profile as theelongated rocker assembly is moved into an engaged position and/or adisengaged position.

In some embodiments, the system may include different types and sizes ofextenders and an adapter for each extender of a first size, and therelated methods of use that can be employed with segmental links andinterlinks to provide a universal surgical implant system for spinesurgeons.

The system of the present disclosure may be understood more readily byreference to the following detailed description of the embodiments takenin connection with the accompanying drawing figures that form a part ofthis disclosure. It is to be understood that this application is notlimited to the specific devices, methods, conditions or parametersdescribed and/or shown herein, and that the terminology used herein isfor the purpose of describing particular embodiments by way of exampleonly and is not intended to be limiting. Also, in some embodiments, asused in the specification and including the appended claims, thesingular forms “a,” “an,” and “the” include the plural, and reference toa particular numerical value includes at least that particular value,unless the context clearly dictates otherwise. Ranges may be expressedherein as from “about” or “approximately” one particular value and/or to“about” or “approximately” another particular value. When such a rangeis expressed, another embodiment includes from the one particular valueand/or to the other particular value Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment. It isalso understood that all spatial references, such as, for example,horizontal, vertical, top, upper, lower, bottom, front, back, left andright, are for illustrative purposes only and can be varied within thescope of the disclosure. For example, the references “upper” and “lower”are relative and used only in the context to the other, and are notnecessarily “superior” and “inferior”.

Further, as used in the specification and including the appended claims,“treating” or “treatment” of a disease or condition refers to performinga procedure that may include administering one or more drugs to apatient (human, normal or otherwise or other mammal), employingimplantable devices, and/or employing instruments that treat thedisease, such as, for example, microdiscectomy instruments used toremove portions bulging or herniated discs and/or bone spurs, in aneffort to alleviate signs or symptoms of the disease or condition.Alleviation can occur prior to signs or symptoms of the disease orcondition appearing, as well as after their appearance. Thus, treatingor treatment includes preventing or prevention of and/or reducing thelikelihood of a certain disease or undesirable condition (e.g.,preventing or reducing the likelihood of the disease from occurring in apatient, who may be predisposed to the disease but has not yet beendiagnosed as having it). In addition, treating or treatment does notrequire complete alleviation of signs or symptoms, does not require acure, and specifically includes procedures that have only a marginaleffect on the patient. Treatment can include inhibiting the disease,e.g., arresting its development, or relieving the disease, e.g., causingregression of the disease. For example, treatment can include reducingacute or chronic inflammation; alleviating pain and mitigating andinducing re-growth of new ligament, bone and other tissues; as anadjunct in surgery; and/or any repair procedure. Also, as used in thespecification and including the appended claims, the term “tissue”includes soft tissue, ligaments, tendons, cartilage and/or bone unlessspecifically referred to otherwise.

The following discussion includes a description of a surgical systemincluding a surgical instrument, related components and methods ofemploying the surgical system in accordance with the principles of thepresent disclosure. Alternate embodiments are also disclosed. Referenceis made in detail to the exemplary embodiments of the presentdisclosure, which are illustrated in the accompanying figures. Turningto FIG. 1A, components of a universal surgical implant system 100 areillustrated, in accordance with the principles of the disclosure.

The components of system 100 can be fabricated from biologicallyacceptable materials suitable for medical applications, includingmetals, synthetic polymers, ceramics and bone material and/or theircomposites. For example, the components of system 100, individually orcollectively, can be fabricated from materials such as stainless steelalloys, aluminum, commercially pure titanium, titanium alloys, Grade 5titanium, super-elastic titanium alloys, cobalt-chrome alloys, stainlesssteel alloys, superelastic metallic alloys (e.g., Nitinol, superelasto-plastic metals, such as GUM METAL® manufactured by ToyotaMaterial Incorporated of Japan), ceramics and composites thereof such ascalcium phosphate (e.g., SKELITE™ manufactured by Biologic Inc.),thermoplastics such as polyaryletherketone (PAEK) includingpolyetheretherketone (PEEK), polyetherketoneketone (PEKK) andpolyetherketone (PEK), carbon-PEEK composites, PEEK-BaSO4 polymericrubbers, polyethylene terephthalate (PET), fabric, silicone,polyurethane, silicone-polyurethane copolymers, polymeric rubbers,polyolefin rubbers, hydrogels, semi-rigid and rigid materials,elastomers, rubbers, thermoplastic elastomers, thermoset elastomers,elastomeric composites, rigid polymers including polyphenylene,polyamide, polyimide, polyetherimide, polyethylene, epoxy, bone materialincluding autograft, allograft, xenograft or transgenic cortical and/orcorticocancellous bone, and tissue growth or differentiation factors,partially resorbable materials, such as, for example, composites ofmetals and calcium-based ceramics, composites of PEEK and calcium basedceramics, composites of PEEK with resorbable polymers, totallyresorbable materials, such as, for example, calcium based ceramics suchas calcium phosphate, tri-calcium phosphate (TCP), hydroxyapatite(HA)-TCP, calcium sulfate, or other resorbable polymers such aspolyaetide, polyglycolide, polytyrosine carbonate, polycaroplaetohe andtheir combinations.

Various components of system 100 may have material composites, includingthe above materials, to achieve various desired characteristics such asstrength, rigidity, elasticity, compliance, biomechanical performance,durability and radiolucency or imaging preference. The components ofsystem 100, individually or collectively, may also be fabricated from aheterogeneous material such as a combination of two or more of theabove-described materials. The components of system 100 may bemonolithically formed, integrally connected or include fasteningelements and/or instruments, as described herein.

The system 100 may include at least one surgical instrument 105 and beemployed, for example, with an open or mini-open, minimal access and/orminimally invasive including percutaneous surgical technique to deliverand fasten an implant at a surgical site within a body of a patient, forexample, a section of a spine. In one embodiment, the components ofsystem 100 may be configured to implant and/or fix a bone fastener, suchas a pedicle screw, or other implants within tissue for a surgicaltreatment to treat various spine pathologies, such as those describedherein.

It should be understood that various aspects disclosed herein may becombined in different combinations than the combinations specificallypresented in the description and accompanying drawings. It should alsobe understood that, depending on the example, certain acts or events ofany of the processes or methods described herein may be performed in adifferent sequence, may be added, merged, or left out altogether (e.g.,all described acts or events may not be necessary to carry out thetechniques). In addition, while certain aspects of this disclosure aredescribed as being performed by a single module or unit for purposes ofclarity, it should be understood that the techniques of this disclosuremay be performed by a combination of units or modules associated with,for example, a medical device.

FIG. 1A is a perspective view that illustrates components of universalsurgical implant system 100. A surgeon when performing surgicaldeformity procedures may need to manipulate the spine (i.e., derotation)and reduce the spinal curvature using an elongated rod to be put inplace using at least one surgical instrument 105 such as, withoutlimitation, an extender and/or a derotator. The system 100 may includean extender and/or a derotator, each with a rocker slide lock 160 and anelongated rocker assembly 140 may be constructed and arranged tolock/connect a head-locking projection 247 (FIG. 15) of the rockerassembly 140 in a bone fastener (not shown) nestled in a head cavity.The arrangement of the rocker slide lock 160 and elongated rockerassembly 140 prevents and/or reduces the likelihood of the head-lockingprojection 247 from becoming inadvertently disengaged from the bonefastener. The system 100 may employ other tools, fasteners, such asdescribed in “CD Horizon® Solera® 5.5/6.0 Spinal System,” by Medtronic,Inc., copyright date 2014, which is incorporated herein by reference inits entirety.

The system 100 may include different types and sizes of instruments,such as without limitation, open-extender types, closed-extender types,short extender types and long extender types. For example, the system100 may include one or more short open-extender instrument assemblies200 that may include a short open-extender 220 and a short reducer 270,as will be described in more detail in relation to FIG. 2. The system100 may include one or more long open-extender instrument assemblies 300that may include a long open-extender 320 and a long reducer 370, aswill be described in more detail in relation to FIG. 3. The system 100may include one or more short closed-extender instrument assemblies 400that may include a short closed-extender 420 and a short reducer 470, aswill be described in more detail in relation to FIG. 4. The system 100may include one or more long closed-extender instrument assemblies 500that may include a long closed-extender 520 and a long reducer 570, aswill be described in more detail in relation to FIG. 5.

The system 100 may include one or more short instrument adapters 700, aswill be described in more detail in relation to FIG. 7. The shortinstrument adapter 700 is use with the short type extenders such as ashort open-extender 220 and a short closed-extender 420. The system 100may include one or more shank-extender instrument assemblies 800, aswill be described in more detail in relation to FIGS. 8A-8B. The system100 may include one or more derotators 900, as will be described in moredetail in relation to FIG. 9.

Referring also to FIG. 1B, a perspective view that illustrates somecomponents of the universal surgical implant system 100 being linkedtogether is shown. The system 100 may include one or more segmental linkassemblies 110 and first and second interlink assemblies 120 and 130.The segmental link assembly 110 may include a segmental link 115 and ahandle 117 configured to attach to the segmental link. The firstinterlink assembly 120 may include interlink element 125 with a handle127 configured to attach to the interlink element 125. The secondinterlink assembly 130 may include interlink element 135 with a handle137 configured to attach to the interlink element 135. In someembodiments, the interlink element 125 may have a different size thanthe interlink element 135. The interlink elements and segmental link maybe generally elliptically shaped.

In some embodiments, an interlink element 125 or 135 may be installed onat least one short open-extender instrument assembly 200, at least oneshort closed-extender instrument assembly 400 or a combination of shortopen-extender instrument assemblies 200 and short closed-extenderinstrument assemblies 400 via the short instrument adapters 700.Although the short extender type surgical instruments have differentconfiguration, the short instrument adapters 700 provides a universalconnection for such short type extenders. The segmental link assemblies110 and first and second interlink assemblies 120 and 130 may bedescribed in U.S. patent application Ser. No. 17/167,415, titled“SURGICAL INSTRUMENT AND METHOD,” incorporated herein by reference inits entirety. Examples of other segmental link assemblies 110 and thefirst and second interlink assemblies 120 and 130 are also, for example,described in “CD Horizon® Solera® 5.5/6.0 Spinal System,” by Medtronic,Inc., copyright date 2014.

FIG. 2 is a perspective view that illustrates a short open-extenderinstrument assembly 200. The short open-extender instrument assembly 200may include a short open-extender 220 and a short reducer 270. The shortopen-extender instrument assembly 200 of FIG. 2 will also be describedin relation to FIGS. 10A-10B, 11A-11C, 12A-12B, and 13. Specifically,FIGS. 10A-10B are front and back views that illustrate the shortopen-extender instrument assembly 200 of FIG. 2. FIG. 11A-11B areperspective views that together illustrate an exploded view of the shortopen-extender instrument assembly 200 of FIG. 2. FIG. 11C is aperspective view that illustrates a rear side of the shortclosed-extender.

The short open-extender 220 may include a body member 222 having a topend 224 and a bottom end 226. The short open-extender 220 may include aleg 228 having a first end integrated with and a leg portion extendingfrom the body member 222.

The short open-extender 220 may include a head cavity 230 (FIG. 10B)formed in a free end 221 of the leg 228 and configured to hold a head(not shown). The head cavity 230 may include a top surface 231 (FIG.11C). A leg 228 may include an elongated channel 232 (FIG. 11A, 11C)that may be formed along a portion of a longitudinal length of the leg228. The channel 232 may include an elongated hole in the leg 228. Thechannel 232 may include a seat 233 integrated with the body member 222.The short open-extender 220 may include at least one adapter fasteningelement 290 formed in body member 222.

The short open-extender 220 may include an elongated rocker assembly 240pivotally coupled within the channel 232 (FIG. 11A, 11C), with anactuation tab 244 and spring 271 in proximity to the body member 222.The seat 233 forms a recess dimensioned to conform to the profile of theactuation tab 244. The spring 271 is adapted to be position between theseat 233 and a medial side of the actuation tab 244. The shortopen-extender 220 may include a collar 250 slidably coupled around thebody member 222. A center axis of the collar 250 may be configured toalign with a longitudinal axis of the body member 222.

FIG. 11A illustrates a lateral side of channel 232. FIG. 11C illustratesa medial side of the channel 232. The lateral side of the channel 232includes an arm limit channel 237, as will be described in more detailin relation to FIGS. 14A-14B.

Referring also to FIGS. 12A, 12B and 13, FIG. 12A is a side view thatillustrates the short open-extender instrument assembly 200 of FIG. 2 inan unlocked state; FIG. 12B is a side view that illustrates the shortopen-extender instrument assembly 200 of FIG. 2 in a locked state; andFIG. 13 is a cross-sectional view along the plane of 13-13 in FIG. 12B.The rocker slide lock 160 (FIG. 1A) may include the collar 250 and theat least one spring-biased bar 261. The collar 250 may have a firstposition that has a clearance from under the actuation tab 244, asdepicted, for example, in FIG. 12A. The collar 250 may have a secondposition that may have a collar portion 251 located between the bodymember 222 and a medial side of the actuation tab 244. This collarportion 251, when under the actuation tab 244 may limit or lock thepivotal motion of the rocker assembly 240 in a direction that preventdisengagement between the head-locking projection 247 from the head.

Referring also to FIGS. 14A-14B and 15, FIG. 14A is a cross-section viewof along the plane 14A-14A in FIG. 13; FIG. 14B is a cross-section viewof along the plane 14A-14A in FIG. 13 but with the instrument inunlocked and disengaged positions; and FIG. 15 is a side view thatillustrates the elongated lever arm 242. When the finger or thumbpresses on the actuator tab 244, the spring 271 may be compressed whichallows the arm 242 to pivot so that the head-locking projection 247 maybe removed from the head cavity 230.

With reference to FIG. 15, the elongated rocker assembly 240 may includean elongated lever arm 242 having a first end 241A and a second end241B. The elongated lever arm 242 may include a first side 243A (e.g.,lateral side) having a sloped end portion 246 at the second end 241B.The lever actuator tab 244 may be formed in the arm 242 on the firstside 243A in proximity to the first end 241A. The elongated lever arm242 may include a second side 243B (e.g., medial side), opposite anddiametrically opposing the first side 243B. The second side 243B of thearm 242 may include a recessed cavity 245, shown in dashed lines, tohold the spring 271. The elongated lever arm 242 may include ahead-locking projection 247 coupled to the second side 243B in proximityto the second end 241B. The projection 247 may be dimensioned to matewith a corresponding slot (not shown) in a bone fastener to lock orsecure a head of the bone fastener, for example.

The elongated lever arm 242 may include a fulcrum 248 (FIG. 10A) coupledto the lever arm 242 in the channel 232. The pivot pin of the fulcrum248 is shown in FIG. 11A, for example The elongated lever arm 242 mayinclude secondary projections 249 integrated in the arm 242 between thehead-locking projection 247 and the fulcrum 248. The secondaryprojections 249 may be diametrically opposing and radiate from sides ofthe arm 242. The secondary projections 249 may radiate essentially 90°relative to a longitudinal length or axis of the arm 242. With referenceto FIGS. 14A and 14B, the projections 249 fit in the limit channel 237to limit movement of the arm 242 so that at least the lower portion ofthe arm 242 remains recessed or flush with the lateral side of the leg228. The limit channel 237 limits the movement of the arm 242, such asmovement of the lower portion of the arm 242 into the head cavity 230.The head-locking projection 247 may extend and project from a plane ofthe second side 243B. Thus, in operation, the profile of the lowerportion of the arm 242 such as at least below the fulcrum 248 may notextend past a lateral side of the leg 228 when the projection is beingdisengaged from the head.

The leg 228 may include a first side 254A (e.g., lateral side) includinga sloped portion 256 having a decreasing slope to the free end 221 ofthe leg 228. The leg 228 may include a second side 254B (e.g., medialside) opposite and diametrically opposing the first side 254A. Thechannel 232 formed in the leg has a depth such that the slopped portion256 of the lever arm 242 is recessed within the depth of the channel232. A length of the lever arm 242 may be recessed or flush with thefirst side 254A of the leg 228 and the actuation tab 244 of lever arm242 may be raised in a plane above the first side 254A.

The short open-extender 220 may include at least one spring-biased bar261, as depicted, for example, in FIGS. 11B, 12A and 13. The collar 250may include diametrically opposing handles 264. A first handle 264 ofthe diametrically opposing handles 264 may be configured aligned withthe elongated lever arm 242. The collar portion 251 extends below thehandles 264.

The body member 222 may include a plurality of holes 267 arranged insuccession along a longitudinal length of the body member 222. The bodymember 222 may include a slide hole 269 diametrically opposing the holes267. The selective positional engagement of the spring-biased bar 261 ofthe collar 250 into a hole of the plurality of holes 267 may establishthe locked position and unlocked position of the rocker slide lock 160(FIG. 1A).

The at least one spring-biased bar 261 snaps the collar 250 to the firstor engaged position when in the first hole and in a second disengagedposition when in a different hole than the first hole. The body member222 may include threads 266 (FIGS. 11A and 11C) formed along an interiorcircumferential surface. The extender's configuration may maintain aminimum profile as the elongated rocker assembly 240 moves into theengaged position and disengaged position, as shown in FIGS. 14A and 14B.In other words, a length of the arm 242 below the actuation tab 244 orbelow the fulcrum 248 may remain substantially recessed in or flush withthe plane of the channel 232 during engaged and disengaged positions.

Referring now to FIG. 11B, the short reducer 270 may include anelongated member 272 having a top end 274 and a bottom end 276 and aremovable reducer pusher 285. The elongated member 272 may include athreaded portion 278 at the upper end of the elongated member 272. Theelongated member 272 below the threaded portion 278 includes anon-threaded portion. The top end 274 may include a knob 280. The knob280 may have a larger circumference than the elongated member 272. Theinternal cavity of the knob 280 may include a tool fastener 282. In someembodiments, the tool fastener 282 may include a hexagonal coupler.

The elongated member 272 may include a circumference configured to fitwithin the body member 222 such that the threads 266 mate with threadsof threaded portion 278. The elongated member 272 may also include aresilient finger 284 with a raised strip element 286 located on thefinger 284. The resilient finger 284 may also include a lip 288 to lockor fasten the removable reducer pusher 285. The raised strip element 286may be a spring press tab. When the user presses the spring press tab,the resilient finger 284 flexes to remove the lip 288 from a lockedposition, so that the pusher 285 may be removed (disassembled) from theelongated member 272. The resilient finger 284 engages and snaps on thereducer pusher 285, as will be described in relation to FIG. 17B. An endof the reducer pusher 285 has a rod seat 289. As the reducer pusher 285moves down, the rod seat 289 may apply a force to push the rod (notshown) into an implanted position.

In operation, a tool (not shown) may be connected to the tool fastener282. The reducer 270 may be configured to be turned in a body member 222via the tool until the reducer pusher 285 of the reducer 270 engages therod (not shown).

The extenders described herein include similar features as thosedescribed above in relation to the short open-extender 220. Anydifferences will be described to permit understanding. The reducer 470(FIG. 4) described below includes similar features as reducer 270 exceptthat the reducer pusher 285 is replaced with reducer pusher 485 (FIG.4).

FIG. 3 is a perspective view that illustrates a long open-extender 320.The long open-extender 320 is similar to the short open-extender 220.Accordingly, for the sake of brevity, generally the differences will bedescribed. The long open-extender 320 may include a body member 322having a top end 324 and a bottom end 326. The long open-extender 320may include a leg 328 having a first end integrated with and a legportion extending from the body member 322. The body member 322 may beelongated and may include an elongated body member section 323. The topof the body member section 323 include threads 366.

The long open-extender 320 may include a head cavity (i.e., head cavity230 of FIG. 10B) formed in a free end 321 of the leg 328 and configuredto hold a head (not shown). A leg 328 may include channel (i.e., channel232 of FIGS. 11A and 11C) formed along a portion of a longitudinallength of the leg 328.

The long open-extender 320 may include an elongated rocker assembly 340pivotally coupled within the channel 232 (FIGS. 11A and 11C), with anactuation tab 444 and spring (i.e., spring 271) in proximity to the bodymember 322. The long open-extender 320 may include a collar 350 slidablycoupled around the body member 322. A center axis of the collar 350 maybe aligned with a longitudinal axis of the body member 322. The collar350 may include diametrically opposing handles 364. A first handle 364of the diametrically opposing handles 364 is configured to be alignedwith the elongated lever arm 342 (i.e., arm 242 of FIG. 15). Thus, nofurther description of arm 342 is needed. The collar portion 351 extendsbelow the handles 364.

The body member includes holes 367 for locking the collar 350 intoposition. The rocker slide lock 160 (FIG. 1A) may include the collar 350and the at least one spring-biased bar (i.e., bar 261). The collar 250may have a first position that has a clearance from under the actuationtab 244, as depicted, for example, in FIG. 12A. The collar 250 may havea second position where the collar portion 251 may be located betweenthe body member 222 and a medial side of the actuation tab 244. Thiscollar portion 251, when under the actuation tab 344 may limit or lockthe pivotal motion of the rocker assembly 340 in a direction that wouldprevent disengagement between the head-locking projection (i.e.,projection 247) from the head.

The operation of the long open-extender 320 is similar to the shortopen-extender 220. Therefore, the operation for locking and unlockingthe head-locking projection (i.e., projection 247) from the head may beessentially the same as described above in relation to FIGS. 12A-12B, 13and FIGS. 14A-14C.

FIG. 4 is a perspective view that illustrates a short closed-extenderinstrument assembly 400. FIG. 4 will also be described in relation toFIGS. 16A-16C. FIGS. 16A-16C are front, side and rear views of the shortclosed-extender instrument assembly of FIG. 4. The short closed-extenderinstrument assemblies 400 may include a short open-extender 420 and ashort reducer 470. The short closed-extender 420 may include a bodymember 422 having a top end 424 and a bottom end 426. The shortclosed-extender 420 may include a first leg 428A and a second leg 428Bthat have diametrically opposing first ends integrated with and a legportion extending from the body member 422. In general, the first leg428A and the second leg 428B are mirror images of the other. The shortclosed-extender 420 may include a head cavity 430 formed in a free end421 of the leg portions of the legs 428A and 428B. The head cavity 430may be configured to hold a head (not shown). Since the first leg 428Aand the second leg 428B are essentially the same, sometimes only one leg(i.e., leg 428A) will be described in detail. The short closed-extender420 may include an adapter fastening element 490 formed in body member422. The adapter fastening element 490 will be described in more detailin relation to the description of the adapter 700 (FIG. 7).

The leg 428A may have a channel 432 formed along a portion of thelongitudinal length of the leg. The short closed-extender 420 mayinclude an elongated rocker assembly 440A pivotally coupled within thechannel 432 of leg 428A, with an actuation tab 444 in proximity to thebody member 422. The leg 428B may have a channel 432 formed along aportion of the longitudinal length of the leg 428B. The elongated rockerassembly 440B may be pivotally coupled to channel 432 of leg 428B. Theelongated rocker assemblies 440A and 440B are essentially the same asrocker assemblies 240. Thus, no further description is needed todescribe the elongated rocker assemblies 440A and 440B.

The short closed-extender 420 may include an elongated rocker assembly440A pivotally coupled within the channel 432 of leg 428A, with anactuation tab 444 in proximity to the body member 422. The shortclosed-extender 420 may include a collar 450 slidably coupled around thebody member 422. The short closed-extender 420 may have a first positionlocated between the body member 422 and the actuation tab 444. Theportion of the collar 450 under the actuation tab 444 may limit pivotalmotion of the rocker assembly 440A, 440B. The second position of thecollar 450 may have a clearance from under the actuation tab 444.Example positions may be seen in FIGS. 12A-12B.

The elongated rocker assembly 440A may include an elongated lever arm442A. The lever arm 442A is essentially the same as lever arm 242described above in relation to FIG. 15. Thus, no further description ofthe arm 442A is needed. The elongated rocker assembly 440B may includean elongated lever arm 442B. The lever arm 442B may also be essentiallythe same as lever arm 242 described above in relation to FIG. 15. Thus,no further description of the arm 442B is needed.

The elongated lever arm 442A or 442B may include a fulcrum 448 pivotallycoupled to the lever arm in the channel 432. The elongated lever arm442A or 442B may include secondary projections (i.e., projections 249)integrated in to the arm between the projection 447 and the fulcrum 448.

The leg 428A may include a first side 454A including a sloped portion456 having a decreasing slope to the free end 421 of the leg 428A. Theleg 428A may include a second side 454B (FIG. 16B) opposite anddiametrically opposing the first side 454A. The channel 432 may beessentially the same as channel 232, thus no further discussion of thechannel 432 is need.

The short closed-extender 420 may include at least one spring-biased bar(i.e., bar 261 of FIG. 11B). The collar 450 may include diametricallyopposing handles 464. A first handle 464 of the diametrically opposinghandles 464 may be aligned with the elongated lever arm 442. The bodymember 422 may include a plurality of holes 467 arranged in successionalong a longitudinal length of the body member 422. The rocker slidelock 160 may include the collar 450 and the at least one spring-biasedbar (i.e., bar 261). The selective positional engagement of thespring-biased bar of the collar 450 into a hole of the plurality ofholes 467 may establish the locked position and unlocked position. Theoperation of the collar 450 relative to body member 422 and theactuation tab 444 may be essentially the same as that described above inrelation to FIGS. 12A-12B.

The short reducer 470 may be essentially the same as short reducer 270previously described in relation to FIG. 11B, except that the removablereducer pusher 485 is used in lieu of pusher 285. The raised stripelement 286 may be used to snap on the pusher 485 to an end of theelongated member 272 or alternatively disassembly such as for cleaning.In operation, as the reducer pusher 485 moves down between legs 428A and428B, a force is applied by pusher 485 to push the rod (not shown)between the legs and into an implanted position. The details of thepusher 485 will be described in more detail in relation to FIG. 17A.

FIG. 17A is a perspective view of the second reducer pusher 485 for theshort reducer 470. The pusher 485 includes a collar 479 configured toreceive an end of the elongated element 272. The collar 479 includes aseat 481 to limit the distance the elongated element 272 can move in thecollar 479. The seat 481 has a reduced diameter relative to the interiorsurface of the upper portion of the collar 479. The pusher 485 alsoincludes diametrically opposing sides 487, which have a length extendingbelow the end of collar 479. In operation, the sides 487 may beconfigured to apply a force to push the rod. The pusher 485 may includeribs (not shown) on the interior surface of collar 479 to latch the lip288 (FIG. 11B) to a corresponding rib, as will be described in FIG. 17B.The spring press tabs 286 (FIG. 11B) allows the lip 288 to clear theribs. Releasing the spring press tab 286 locks the second reducer pusher485 to the elongated element 272.

FIG. 17B illustrates top perspective view of the first reducer pusher285 for the short reducer 270. The first reducer pusher 285 includes acollar 279 with a seat 281 at the end of the collar 279. The seat 281has a reduced diameter relative to the interior surface of the upperportion of the collar 279. The interior surfaces of the collar 279 haveribs 297 and 299, at least one of which may be configured to engage lip288 to secure the pusher 285 to the elongated member 272. The pusher 285includes sides 287 for applying a force of pressure to the rod.

FIG. 5 is a perspective view that illustrates a long closed-extender520. The long closed-extender 520 is similar to the shortclosed-extender 420. Thus, for the sake of brevity, the differences willbe described. The long closed-extender 520 may include a body member522. The body member 522 may include an elongated body member section523. The top of the body member section 523 may include threads 566. Thelong closed-extender 520 may include legs 528A and 528B, which aremirror images of each other. The ends of the legs form a head cavity530.

Each leg 528A and 528B may include an elongated rocker assembly 540 withan elongated lever arm 542. The lever arm 542 is essentially the same aslever arm 242 described above in relation to FIG. 15. Thus, no furtherdescription of the arm 542 is needed.

The elongated lever arm 542 may include a fulcrum 548 pivotally coupledto the lever arm 542 in the channel 532. The elongated lever arm 542 mayinclude secondary projections (i.e., projections 249) integrated intothe arm between the projection 547 and the fulcrum 548 of the same arm.

The long closed-extender 520 may include at least one spring-biased bar(i.e., bar 261 of FIG. 11B). The collar 550 may include diametricallyopposing handles 564. A first handle 564 of the diametrically opposinghandles 564 may be aligned with the elongated lever arm 542. The bodymember 522 may include a plurality of holes 567 arranged in successionalong a longitudinal length of the body member 522. The rocker slidelock 160 may include the collar 550 and the at least one spring-biasedbar (i.e., bar 261). The selective positional engagement of thespring-biased bar of the collar 550 into a hole of the plurality ofholes 567 may establish the locked position and unlocked position. Theoperation of the collar 550 relative to body member 522 and theactuation tab 544 may be essentially the same as that described above inrelation to FIGS. 12A-12B.

FIG. 6 is a perspective view that illustrates a long reducer 670. Thelong reducer 670 may include an elongated member 672 having a top end674 and a bottom end 676 and a removable reducer pusher 685. Theelongated member 672 may include a threaded portion 678 at the upper endof the elongated member 672. The top end 674 may include a knob 680. Theknob 680 may have a larger circumference than the elongated member 672.The internal cavity of the knob 680 may include a tool fastener 682. Insome embodiments, the tool fastener 682 may include a hexagonal coupler.The longer reducer may allow for larger displacement of travel.

The elongated member 672 may include a circumference that fits withinthe body member 522 such that the threads 566 mate with threads ofthreaded portion 678. The reducer pusher 685 may be affixed to the endof the elongated member 672 via upper collar 677, in some embodiments.Alternately, the resilient finger arrangement described in relation tothe short reducer 270 may be used. The reducer pusher 685 may have a rodseat 689. As the reducer pusher 685 moves down, the rod seat 689 mayapply a force to push the rod (not shown) into an implanted position.

FIG. 7A is a perspective view that illustrates a short instrumentadapter 700. FIG. 7B is a perspective view that illustrates a shortinstrument adapter 700 with the lever 725 and spring 726 separated. Theadapter 700 may be configured to connect to open and closed type shortreducers and short-extenders. In some embodiments, the adapter 700 maybe part of the instrument assemblies with the short reduces andshort-extenders. The adapter 700 may include a first interface bodyportion 720 that may include a hollow cavity dimensioned to slide on topof and fit around an outer perimeter of the handles 264 or 464integrated in to the collar 250 or 450.

The adapter 700 may include a second interface body portion 722integrated with the first interface body portion 720. The secondinterface body portion 722 may include a tubular member dimensioned tofit over and around that portion of the reducer 270 or 470 above thebody member 222 or 422. The adapter 700 may include an adapter lever 725pivotally coupled to the first interface body portion 720. The adapterlever 725 may have a first position, as shown in FIG. 7A, to engage theadapter fastening element 290 (FIG. 11A) to lock the adapter 700. Theadapter lever 725 may have a second position to disengage from theadapter fastening element 290, which unlocks the adapter 700. After theadapter is unlocked, the adapter 700 may be removed from the body member222 or 422 and the short reducer 270 or 470. The lever 725 may bepivoted about pivot hole 737 and pin 730 within lever cavity 740. Thelever 725 includes an upper lever portion 734 and a bottom lever portion735. In the first position, protrusion 736 engages hole 290 (FIG. 2) tolock the adapter 700 to the assembly 200. When the lever 725 is in asecond position, the adapter 700 may be unlocked from the assembly 200and may be removed. In the second position, a user may apply pressure tothe upper lever portion 734 to pivot the lever 725 forward in in adirection away from and out of the lever cavity 740

FIG. 8A is a perspective view that illustrates a shank-extenderinstrument assembly 800. The shank-extender instrument assembly 800 mayinclude an outer sleeve 822 having a first portion 824, a second portion826 and a third portion 828. The first portion 824 may have a firstdiameter and a second portion 826 with a second diameter. The outersleeve 822 includes a distal end 823. The first diameter may be smallerthan the second diameter. The outer sleeve 822 may include anintegration zone 830, which may be gradually slopped from an end of thesecond portion 826 to the first portion 824. The third portion 828 mayhave a third diameter that is larger than the second diameter. The thirdportion 828 may be a knob. The outer sleeve 822 may have a secondintegration zone 831 between the second portion 826 and the thirdportion 828. A free (bottom) end of the first portion 824 may includeslots 821. In operation, the outer sleeve 822 may serve as a collar.

With reference also to FIG. 8B, the shank-extender instrument assembly800 may include an middle sleeve 840 having a first portion 844, asecond portion 846, a third portion 848 and a fourth portion 850. Thefirst portion 844 may have a first diameter and a second portion 846with a second diameter. The first diameter may be smaller than thesecond diameter. The third portion 828 may have a third diameter that islarger than the second diameter. The fourth portion 850 may have afourth diameter larger than the third dimeter and may be a knob.

The first portion 844 has a plurality of slots 849 formcircumferentially therearound in spaced relation. The slots 849 may beconfigured to align with slots 821 (FIG. 8A). The slotted first portion844 is slotted like a collet, for example, to allow it to expand, suchas when being received over a head of a bone fastener, as depicted, forexample, in FIG. 20D. The first portion 844 may be integrated into alower portion of the second portion 846 such that the distal end of themiddle sleeve 840 has a diameter larger than the first diameter. Thesecond portion 846 may include a channel 847. Instrument assembly 800may allow derotation to be applied directly to the shank. Theshank-extender instrument assembly 800 may have the ability to turn a“shank” into a fixed angle implant and manipulate directly off of theshank.

The shank-extender instrument assembly 800 may include an elongatedshaft 860 having a length of shaft body 862. A top end 864 of the shaftbody 862 may be threaded. The bottom end 866 of the shaft body 862 mayhave a reduced diameter relative to the diameter of the shaft body 862.The bottom end 866 may be configured as a connector to connect to a headof a bone fastener (FIG. 20D). The shank-extender instrument assembly800 may include pins 863 configured to be received in channel 847.

The shaft body 862 may be configured to be received in the middle sleeve840. The shank-extender instrument assembly 800 may include a topinstrument fastener 870 to which the top end 864 may be affixed usingthe threads. The spring 872 may be received and housed below the thirdportion 848 between the middle sleeve 840 and an interior surface of theouter sleeve 822, as depicted, for example, in FIGS. 20B-20D. The topinstrument fastener 870 may include a fastener element 882 (FIG. 8A)such as a hexagonal coupler. The operation of the shank-extenderinstrument assembly 800 will be described in more detail in relation toFIGS. 20A-20D.

FIG. 9A is a perspective view that illustrates an apical derotator 900.FIG. 9B is a side view that illustrates an apical derotator 900 of FIG.9A. The derotator 900 is similar to a long type extender but without areducer. The derotator 900 includes a body member 922. The body member922 may include an elongated body member section 923. The derotator 900may include leg 928 and support 929 that may be parallel to leg 928. Theends of the leg 928 and support 929 form a head cavity 930, such as tocouple to the bone fastener 1900 (FIG. 19). The leg 928 and support 929may be fastened together by integrated cross support 929. The apicalderotator 900 includes elongated channel 927A above the cross support929 and channel 927B below the cross support 929.

Leg 928 may include an elongated rocker assembly 940 with an elongatedlever arm 942. The lever arm 942 is essentially the same as lever arm242 described above in relation to FIG. 15. Thus, no further descriptionof the arm 942 is needed. The elongated lever arm 942 may include afulcrum 948 pivotally coupled to the lever arm 942 in the channel 932.The elongated lever arm 942 may include secondary projections (i.e.,projections 249) integrated in the arm between the head-lockingprojection (i.e., projection 247) and the fulcrum 548 of the arm. Thederotator 900 may have a collar 950 (i.e., collar 250) and spring-biasedbar (i.e., bar 261). The rocker slide lock 160 (FIG. 1A) may include thecollar 950 and the at least one spring-biased bar (i.e., bar 261). Theoperation of collar 950 relative to body member 922 is similar to collar250 and body member 222, as shown and described in relation to at leastFIGS. 12A and 12B. Thus, no further discussion of the collar 950 will beneeded.

FIG. 18 is an end view of the derotator 900 of FIG. 9A. The derotator900 does not have a reducer. The derotator 900 may be configured toattach to the head (i.e., head 1920) and allows for derotationmanipulation. The head cavity 930 does not have a top surface (i.e. topsurface 231 of FIG. 11C), so it can slide down over a reduction screw orother tabbed implant.

FIG. 19 is a side view that illustrates a prior art bone fastener 1900.The bone fastener 1900 may be a reduction screw. The reduction screw hasa head 920, which may be extended relative to other bone fasteners. Thereduction screw has extended tabs that allow a larger window to captureand slowly reduce the spinal rod, which can be broken off when the rodreduction is completed. An example reduction screw is described in “CDHorizon® Solera® 5.5/6.0 Spinal System,” by Medtronic, Inc., copyrightdate 2014.

FIG. 20A is a perspective view that illustrates the shank-extenderinstrument assembly 800 of FIG. 8A and a bone fastener 15. FIG. 20B is across-sectional view along the plane 20B-20B of FIG. 20A. FIG. 20C is across-sectional view, as shown in FIG. 20B, with the bone fastener 15attached to the shank-extender instrument assembly 800 in an extendedposition. FIG. 20D is a cross-sectional view, as shown in FIG. 20B, withthe bone fastener 15 attached to the shank-extender instrument assembly800 in a retracted position. The bone fastener 15 may include a shank 17and a head 19. The head 19 may include a notch 20 to connect to aninstrument or tool. The notch 20 may be configured to provide anon-rotational connection between the head 19 and a connector (i.e.,bottom end 866) of an instrument assembly 800.

In certain uses, for example, if in FIG. 20A the shank 17 is in avertebral body and surgeon is holding instrument assembly 800, to attachthe instrument assembly 800 to the shank 17, the collar (i.e., an outersleeve 822) may be pulled back, as depicted, for example, in FIG. 20B,and the bottom end 866 (i.e., connector) may be caused to be pushed outof distal end 823 of the collar and onto the shank 17, as depicted, forexample, in FIG. 20C. In this disclosure, the term “pulled back” is inthe direction toward the top instrument fastener 870. The middle sleeve840 may be slotted (like, for example, a collet) to allow it to expandand snap over the head 19 of shank 17, as disclosed, for example, inFIG. 20D. The collar (i.e., an outer sleeve 822) may be released, and aspring force from spring 872 pushes it back down to lock and/or connectthe shank 17 in place.

The elongated shaft 860 can be threaded in or out to adjust the tensionapplied to the shank 17 when it is locked and/or connected in theinstrument assembly 800. The fastener element 882 (i.e., hexagonalcoupler) may be formed in the top instrument fastener 870 to allow thesurgeon to use another instrument or tool to apply additional torquewhen adjusting the tension. Once the shank 17 is locked and/or connectedinto place, the surgeon can use hands or a segmental link assembly 110and/or interlink assembly 120 or 130 as depicted, for example, in FIGS.1A-1B, to manipulate the screws.

What is claimed is:
 1. A system, comprising: a plurality of surgical instruments of different types, each surgical instrument comprises: a body member having a top end and a bottom end; a leg having a first end integrated with and a leg portion extending from the body member; a head cavity formed in a free end of the leg portion and configured to hold a head; an elongated channel formed along a longitudinal length of the leg; an elongated rocker assembly pivotally coupled within the channel and comprising a spring actuation tab in proximity to the body member; and a collar slidably coupled around the body member and having a first position located between the body member and the actuation tab such that a portion of the collar is under the actuation tab to limit pivotal motion of the rocker assembly and a second position of the collar has a clearance from under the actuation tab.
 2. The system of claim 1, wherein the elongated rocker assembly comprises: an elongated lever arm having a first end and a second end, the elongated lever arm includes: a first side having a sloped end portion at the second end of the lever arm, the lever actuator tab formed in the arm on the first side in proximity to the first end of the arm, a second side, opposite and diametrically opposing the first side, a head-locking projection coupled to the second side in proximity to the second end, a fulcrum pivotally coupled the lever arm in the elongated channel, and secondary projections integrated into the arm between the head-locking projection and the fulcrum, wherein the head-locking projection extends and projects from a plane of the second side.
 3. The system of claim 1, further comprising at least one spring-biased bar, wherein: the collar comprises: diametrically opposing handles, a first handle of the diametrically opposing handles is configured to be aligned with the elongated lever arm; and the body member comprises: a plurality of holes arranged in succession along a longitudinal length of the body member, the at least one spring-biased bar snaps the collar to the first position when in the first hole and in a second position when in a different hole than the first hole, and threads formed along an interior circumferential surface.
 4. The system of claim 1, wherein: the leg comprises: a first side including a sloped portion having a decreasing slope to the second end of the leg; and a second side opposite and diametrically opposing the first side, wherein: the elongated channel formed in the leg has a depth; and the slopped portion of the lever arm is recessed within the depth of the channel, the lever arm is recessed or flush with the first side of the leg and the actuation tab raised in a plane above the first side.
 5. The system of claim 1, wherein the instrument comprises an extender.
 6. The system of claim 1, wherein the leg is a first leg; and further comprising a second leg having a first end integrated with and a second leg portion extending from the bottom end of the body member, the second leg diametrically opposes the first leg; a channel formed along a portion of a longitudinal length of the second leg; and a second elongated rocker assembly pivotally coupled within the channel of the second leg and comprising a second actuation tab in proximity to the body member, wherein: the collar slidably is coupled around the body member and the first position located between the body member and the second actuation tab such that a portion of the collar is under the second actuation tab to limit pivotal motion of the second rocker assembly and the second position has a clearance from under the second actuation tab; and a portion of the head cavity is also formed also in the second end of the second leg and configured to hold the head.
 7. The system of claim 1, wherein the plurality of instruments comprises two or more of: a derotator; an short open-extender; a short closed-extender; a long open-extender; and a long closed-extender.
 8. The system of claim 7, wherein at least one of the plurality of instruments comprises the short open-extender, the short closed-extender or both the short open-extender and the short closed-extender; and further comprising at least one adapter, each adapter configured to increase a length of one of the short open-extender or the short closed-extender.
 9. The system of claim 8, further comprising: a segmental link assembly comprising a segmental link and a handle configured to attach to the segmental link; a first interlink assembly comprising first interlink element having a first handle configured to attach to the interlink element; and a second interlink assembly comprising a second interlink element having a second handle configured to attach to the second interlink element, wherein the first interlink element has a first size and the second interlink element has a second size different from the first size.
 10. The system of claim 9, wherein the first interlink elements and second interlink element are configured to attach to the adapter.
 11. The system of claim 8, wherein the adapter includes a locking lever to lock to the body member at a location above the collar.
 12. The system of claim 8, further comprising: a first short reducer configured to interface with the short open-extender; and a second short reducer configured to interface with the short closed-extender.
 13. The system of claim 12, wherein each of the first short reducer and the second short reducer comprises: an elongated member having a first end, a threaded portion, a non-threaded portion and a second end; a fastener integrated into the first end; a resilient finger formed in the non-threaded portion; a spring press tab formed on the resilient finger to flex the finger; and a lip at a free end of the finger.
 14. The system of claim 13, wherein: the first short reducer comprises: a first reducer pusher configured to be coupled to the elongated member by the lip; and the second short reducer comprises: a second reducer pusher configured to be coupled to the elongated member by the lip.
 15. The system of claim 8, wherein at least one of the plurality of instruments further comprises the long open-extender, the long closed-extender or both the long open-extender and the long closed-extender; and further comprising: a first short reducer configured to interface with the short open-extender, a second short reducer configured to interface with the short closed-extender, a first long reducer configured to interface with the long open-extender, and a second long reducer configured to interface with the long closed-extender.
 16. The system of claim 7, wherein the derotator comprises an apical derotator.
 17. The system of claim 1, further comprising a shank-extender instrument assembly.
 18. The system of claim 1, further comprising a rocker slide lock having the collar constructed and arranged to lock a head-locking projection of the rocker assembly in the head nestled in the head cavity.
 19. The system of claim 1, wherein: the elongated channel comprises an arm limit channel; and the elongated rocker assembly comprises: an elongated lever arm having a first end and a second end, the elongated lever arm includes: a first side having a sloped end portion at the second end of the lever arm, with the actuation tab formed in the arm on the first side is in proximity to the first end of the arm, a second side, opposite and diametrically opposing the first side, a head-locking projection integrated into the second side in proximity to the second end, a fulcrum pivotally coupling the lever arm in the elongated channel, and secondary projections integrated into the arm between the head-locking projection and the fulcrum, wherein the secondary projections are coupled into the arm limit channel to limit the movement of the arm below the fulcrum within the elongated channel
 20. A method, comprising: providing the system of claim 1; providing a plurality of reducers; coupling a respective one reducer to a respective one surgical instrument to form an instrument assembly with a rocker slide lock; using the instrument assembly for reducing a rod in a head of a bone fastener; and prior to reducing the rod, locking the head with rocker slide lock.
 21. The method of claim 20, further comprising: using a respective one instrument of the system of claim 1 to perform derotation.
 22. A method, comprising: using a respective one instrument of the system of claim 1 to perform derotation; and using a respective one instrument of the system of claim 1 with a reducer to perform rod reduction. 